1. Field Of The Invention
This invention relates to the field of purifying water. More particularly, the invention relates to a method and apparatus for removing non-volatile contaminants from contaminated water. The present invention is particularly well suited for obtaining purified water from radioactively contaminated areas.
2. Description of The Background
The purification of contaminated liquids, particularly water, has been attempted throughout history.
A large variety of equipment and methods have been reported for the purification of liquids such as water, particularly directed towards the purification of sewage, the desalination of water and the removal of salts from brines.
Most of the prior art processes have proven costly since they involve the utilization of cumbersome machinery and equipment, require transportation of the liquid to be purified to the processing plant, and the like.
The literature, however, is scanty when it comes to the in situ purification of liquids such as water by means of a simple and inexpensive system.
U.S. Pat. No. 4,326,923 to Mortenson describes an apparatus for distilling water from sea water. This apparatus consists of a column packed with layers of low capillary-activity materials such as sand and various metallic particles to attain an upwardly--increasing thermal conductivity, and a condenser maintained at a lower temperature than the column. Some layers may optionally contain cellulosic materials. The water is heated with solar energy, vaporized within the column, and then condensed and released to a tank.
A process for concentrating brine pumped from underground ore deposits is described in U.S. Pat. No. 3,966,541 to Sadan. This process concentrates brine by solar evaporation of a volume of water pumped from the ore deposits to attain a desired concentration of salts, and returning the concentrated brine to the underground ore reservoirs.
U.S. Pat. No. 4,333,831 to Petzinger relates to an apparatus for sewage treatment having a plurality of vertical evaporation tanks ending at the top in a rotary ventilator to prevent any water back-up or entry of rain.
U.S. Pat. No. 4,172,767 to Sear discloses a water purification system consisting of a closed evaporation tank heated by solar energy and a blower channeling vaporized water into a colder pipe and out of the tank area where condensation occurs.
U.S. Pat. No. 1,082,411 to Cozzolino relates to an apparatus for evaporating liquids such as beers and malt-like extracts, and semi-liquids such as crushed fruits and vegetables, jams and the like. The apparatus consists of a vessel to contain the liquid provided with an upper outlet to release vapor, a means for heating the liquid contained in the vessel and a series of fabric sheets which the evaporating liquid traverses in its upward movement towards the outlet.
U.S. Pat. No. 3,257,291 to Gerber relates to a desalination apparatus consisting of an elongated solar-heated evaporator positioned at an angle with respect to the horizontal to foster the downward flow of sea water, means for blowing air lengthwise inside the evaporator to carry vaporized water to a condenser which is cooled by the concentrated sea water, and means for withdrawing humidified air and condensing fresh water.
U.S. Pat. No. 3,702,762 to Low discloses an apparatus for vaporizing a metal to remove impurities therefrom. The apparatus consists of a U-shaped conduit having a center reservoir provided with heating coils to contain a liquid metal, an upwardly extending up-stream arm also provided with heating coils to vaporize the metal, a plurality of capillary tubes connected in a continuous fashion which are positioned inside the conduit between the reservoir and the up-stream arm of the conduit to conduct the vaporized metal from the up-stream arm through the reservoir and into an upwardly oriented down-stream arm of the conduit provided with cooling coils to liquify the metal and allow for vaporized impurities to be upwardly drawn by a vacuum line out of the down-stream arm.
U.S. Pat. No. 4,595,460 to Hurt describes an apparatus and method for distilling a liquid consisting of a reservoir having two liquid columns which communicate at the bottom and the top and have different levels of liquid. A higher level of liquid is attained in one of the columns by aeration. The liquid vaporized by solar energy from the column having the higher level of liquid leaves through the top of the reservoir and goes to a condenser where it is liquified.
Thus, there still exists a need for a simple method and apparatus for decontaminating water which can be easily applied to the site where the contaminated water is located, is simple to implement and requires substantially no energy input.